Gas turbine, the core equipment of the power plant, is capable of rapid starting operation and has less carbon dioxide emission than coal power plant. So it has the advantage of being eco- friendly. In order to increase the efficiency of these gas turbines, the turbine inlet temperature has steadily increased and to ensure the safety of the gas turbine, means for protecting parts exposed to high temperatures have also been developed. Protective coating technology is one of them, which plays the role of lowering the temperature of the base metal and preventing oxidation and corrosion. In this paper, thermal fatigue test simulating the operation environment was conducted using the Amdry 9951 protective coating powder applied to the HPT Heat Shield for the Alstom GT 24 gas turbine and the performance before and after the thermal fatigue test was evaluated and examined by adhesive strength test and SEM (EDS) analysis.